The present invention relates generally to ovens and, more particularly, to an oven with a damped oven door mounting assembly.
Oven doors are generally constructed to be relatively rigid to facilitate forming an adequate seal about the heating chamber opening. Further, oven doors typically include various forms of insulation features, such as insulating materials and/or voids (e.g., dead air spaces) therein. Consequently, oven doors tend to be relatively bulky and heavy. To facilitate manual movement of the door, such as closing the door, (which requires moving the door from a generally horizontal position toward a vertical position, i.e., requiring the lifting of a substantial portion of the weight of the door) oven doors hinges often utilize a spring connected about the hinge to bias movement of the door relative to the oven in one direction, or the other, or both.
Such a hinge for an oven door is described in Leland, U.S. Pat. No. 3,450,125. Leland discloses a hinge for an oven door that allows the door to be moved between an open position, a closed position, and broiler stop position (partially open position adjacent closed position). Additionally, the hinge is provided with a spring to bias the door towards the closed position.
A hinge for an oven door, as described in Leland is advantageous since manual movement of the door is assisted via the spring. However, if not at least partially manually controlled, upon closing the spring biasing the door toward the closed position will generate excessive momentum causing the door to xe2x80x9cslamxe2x80x9d against the oven frame. Consequently, the door and oven frames are subject to fatigue and impact damage. More specifically, as the door swings toward the closed position about the hinge, the weight acting on the door decreases as the door becomes more vertically oriented. At a point prior to conventional (and operable) broiler stop positions, the spring force acting on the door towards the closed position overcomes the force (weight of the door) on the door acting towards the open position and effects movement of the door towards the closed position. As such, the spring increases the momentum of the closing door and xe2x80x9cslamsxe2x80x9d the door against the oven frame. Even with an intermediate (broiler) stop provided, as with Leland, the spring driven momentum of the door, when manually uncontrolled through this range of movement, is sufficient to prevent stoppage at the intermediate stop and significantly impact the door against the oven frame. It is, of course, possible to manually move the door to the closed position and thereby prevent impact damage however, given inherent circumstances in a typical kitchen, it is often inconvenient at best for a user to commit a hand to closing the door.
Herbster (U.S. Pat. No. 2,124,349) discloses an oven door operating device that utilizes a spring to facilitate closing the door and a supposed xe2x80x9cbufferxe2x80x9d to decrease momentum of the door as it approaches the fully open and closed positions. This device is advantageous in that the door and oven are seemly protected from excessive impacts. However, the device poses several handicaps when presented with the current state of the art.
First, the device is foot controlled by way of a pair of pedals. This may prove useful in providing hands-free operation of the door, however significantly increases the force applied to the door and momentum thereof. Herbster""s foot pedals seem to promote excessive force on the door, especially when moving into the extreme positions (opened and closed positions). To reduce instances of excessive impacts, Herbster provides a buffer to reduce the momentum of the door as it moves into the fully open and fully closed positions.
The device of Herbster is quite bulky and primarily mounted to the frame of the oven. While this arrangement effectively hides the device from view and hindrance, it requires substantial space within the oven frame to accommodate mounting of the device therein. Further, ovens of the type described in Herbster generally include a separate broiler portion. As such, Herbster makes no reference to supplying a broiler stop.
As stated previously, Herbster""s device supplies a buffer to cushion the impacts of the door. As shown and described in Herbster, the buffer acts to resist motion in either direction of movement of the door (towards the open position and towards the closed position, corresponding to relative axial movement of the piston). As such, Herbster""s device resists manual movement of the door, so as to increase the effort required to manually effect movement of the door, especially towards the open position, wherein the spring provides further resistance to movement.
Furthermore, Herbster""s buffer, as shown and described, acts as a resilient spring in that the compression of air therein provides the resisting force of the damper. There is provided an inlet check valve at each end of the buffer to allow an inflow of air. As Herbster does not address the problem of the increasing volume of the piston arm within the cylinder as the piston moves downwardly, it is submitted that movement of the door toward the open position, corresponding to the downward movement of the piston within the buffer, will produce relatively greater resistive force than movement of the door toward the closed position. This is highly unfavorable since movement of the door toward the open position is further resisted by the spring. It is further submitted that since no outlet within the cylinder is provided, subsequent movements of the door will cause a pressure increase within the buffer due to the inability of air to escape the cylinder. When a relatively high pressure is reached within the buffer, the suction pressure produced will be insufficient to actuate the inlet valves. At this point, movement of the door toward the open position, corresponding to downward movement of the piston and an increasing volume of piston arm within the cylinder, will be substantially resisted, as the buffer would then act as a spring biasing the door toward the closed position.
The present invention avoids these limitations by providing an oven comprising an oven assembly, which defines an oven chamber within which heatable items can be heated and an access opening communicating with the oven chamber. An oven door assembly is mounted on the oven assembly for movement between a generally vertically extending closed baking operating position, a slightly inclined partially open broiling operating position, and a generally horizontally extending open position.
The oven door assembly defines substantially enclosed restricted spaces within opposite ends thereof, within which a pair of horizontally spaced door mounting assemblies extend. Each of the door mounting assemblies include a mounting member extending from an associated space and are detachably fixedly secured to the oven assembly. Each of the door mounting assemblies are also pivotally connected to the door assembly enabling the door assembly to be pivotally moved with respect to the oven assembly between the operating positions and the open position thereof.
Each of the door mounting assemblies includes a spring biased mechanism within an associated space. The spring biased mechanisms are constructed and arranged to enable the oven door assembly to be moved by the weight thereof toward and into the open position thereof when in a first range of movement adjacent the open position. The spring biased mechanism also enables the oven door assembly to be biased toward and into the broiling position by the spring biased mechanism when in a second range of movement adjacent the broiling position thereof. Further, the spring biased mechanism enables the oven door assembly to be biased toward and into the baking position by the spring biased mechanism when in a third range of movement adjacent the baking position.
The oven includes a manually engagable structure on the oven door assembly, which is constructed and arranged to enable a user to manually control movement of the oven door assembly within all of the ranges.
The pair of door mounting assemblies includes a damper assembly within an associated space. The damper assembly is constructed and arranged to provide resistance to the movement of the oven door assembly within the second and third ranges to limit the rate of movement of the oven door assembly toward the broiling and baking positions.
In a preferred embodiment, substantially less resistance to the movement of the oven door assembly is provided toward the open position (away from the baking position) in comparison with the greater resistance to movement toward the baking position.